However, though researchers have been able to show how RNA’s component molecules, called ribonucleotides, could assemble into RNA, their many attempts to synthesize these ribonucleotides have failed. No matter how they combined the ingredients — a sugar, a phosphate, and one of four different nitrogenous molecules, or nucleobases — ribonucleotides just wouldn’t form.

Sutherland’s team took a different approach in what Harvard molecular biologist Jack Szostak called a “synthetic tour de force” in an accompanying commentary in Nature.

“By changing the way we mix the ingredients together, we managed to make ribonucleotides,” said Sutherland. “The chemistry works very effectively from simple precursors, and the conditions required are not distinct from what one might imagine took place on the early Earth.”

Like other would-be nucleotide synthesizers, Sutherland’s team included phosphate in their mix, but rather than adding it to sugars and nucleobases, they started with an array of even simpler molecules that were probably also in Earth’s primordial ooze.

They mixed the molecules in water, heated the solution, then allowed it to evaporate, leaving behind a residue of hybrid, half-sugar, half-nucleobase molecules. To this residue they again added water, heated it, allowed it evaporate, and then irradiated it.

At each stage of the cycle, the resulting molecules were more complex. At the final stage, Sutherland’s team added phosphate. “Remarkably, it transformed into the ribonucleotide!” said Sutherland.

According to Sutherland, these laboratory conditions resembled those of the life-originating “warm little pond” hypothesized by Charles Darwin if the pond “evaporated, got heated, and then it rained and the sun shone.”

Neat stuff btw, I wonder when that RNA bands starts replicating itself. I guess there's still some road from RNA to life.

That's kind of the problem. The RNA world theory isn't all that far fetched but the self replication of RNA isn't exactly known - at least from things solely in the primordial soup and no proteins or activation factors. There have been some recent studies into ribozymes that can self replicate each other.

So because it takes time to discover things such as this, it's somehow invalidated?

That's like saying all those years it tool science to prove Religion wrong in that the world isn't the center of the Solar System/Universe is somehow invalidated.

I mean ... what kind of thinking is this?

He doesn't understand what the term structure means for RNA. He likely means types. Synthesis of those types isn't the problem. The whole point of the science trying to prove the RNA World hypothesis is to form a progression from the primordial soup to a autocatalytic RNA to life composed of only RNA. They are also concurrently working on the evolution of RNA to DNA for storage purposes with the remnants thought to be ribosomal RNA.

Maybe I don't understand this stuff enough (I don't), but what's preventing these ribonucleotides that exist today from doing this same process out in nature? Is it because the conditions of the earth are so dramatically different that we can't just drop some ribonucleotides out in a pond and observe how it develops?